Apparatus for measuring magneto-optical effect

Abstract

An apparatus for measuring magneto-optical effect includes a light source 102, a spectroscope 120, a first polarizer 150 to polarize the light with a required wavelength taken out by the spectroscope 120, means 172 for applying magnetic field on a sample 176, a second polarizer 156 to admit the light transmitted or reflected by a sample 176 to pass, a photo-detector 162 for detecting intensity of light that has passed the second polarizer 156. The light source 102 includes a heavy hydrogen lamp and the spectroscope does not contain a lens and/or prism. A light path from the light source to the photo-detector is housed in a container, and the container is filled with a gas containing no oxygen.

What is claimed is: 
     
       1. An apparatus for measuring magneto-optical effect, comprising: a light source including a heavy hydrogen lamp for emitting light;   a spectroscope for separating light emitted by the light source into a spectral component of a preselected wavelength, wherein the spectroscope does not include any of a lens and a prism;   a first polarizer for polarizing the separated light spectrum taken out by the spectroscope and transmitting the light from the first polarizer to irradiate a sample;   means for applying a magnetic field to the sample;   a second polarizer for receiving light from the first polarizer which is one of transmitted through and reflected by the sample;   a photo-detector for detecting an intensity of light transmitted by the second polarizer   wherein a light path from the light source to the photo-detector is housed in a container   having an oxygen free atmosphere therein.   
     
     
       2. The apparatus as defined in claim 1, further comprising: means for modulating, at a specific frequency, light irradiated on the sample; and   means for obtaining from a value corresponding to the intensity detected by said detector the intensities of a direct current component, modulation frequency component and frequency component twice as high,   whereby simultaneous measurements of rotation angle and ellipticity of the magneto-optical effect is permitted.   
     
     
       3. The apparatus as defined in claim 1, wherein said light source further includes a second lamp for emitting light with a wavelength range of longer than those of the heavy hydrogen lamp, and wherein said spectroscope is capable of selecting the lamp from which the light comes so that measurements over a wide wavelength range is permitted. 
     
     
       4. The apparatus as defined in claim 1, wherein a light condensing system is made up of reflecting mirrors without containing lenses. 
     
     
       5. The apparatus as defined in claim 1, further comprising a concave reflecting mirror positioned to reflect the light from the light source to the spectroscope, the concave reflecting mirror comprising polished quartz coated with platinum. 
     
     
       6. The apparatus as defined in claim 5, wherein the concave mirror further comprises a top coating of Al--MgF 2 . 
     
     
       7. The apparatus as defined in claim 1, further comprising a sample holder including means for heating and cooling the sample. 
     
     
       8. The apparatus as defined in claim 1, wherein the spectroscope comprises three diffraction gratings. 
     
     
       9. The apparatus as defined in claim 8, further comprising a rotary base on which the spectroscope is mounted, wherein the pre-selected wavelengths are chosen by rotating the rotary base. 
     
     
       10. An apparatus contained within a substantially oxygen-free environment for measuring magneto-optical effects, the apparatus comprising: a light source comprising a heavy hydrogen lamp;   a spectroscope, wherein the spectroscope transmits a selected portion of the light from the light source, the selected portion of light having pre-selected wavelengths, wherein the spectroscope does not include any of a lens and a prism; and   a photo-detector for measuring an intensity of light received from a sample irradiated with light from the spectroscope, wherein the light received by the photo-detector is one of light reflected by and light transmitted from the sample.   
     
     
       11. The apparatus as defined in claim 10, further comprising: first and second polarizers, the first polarizer being disposed between the spectroscope and the light source and the second polarizer being disposed between the sample and the photo-detector; and   means for applying a magnetic field to the sample.   
     
     
       12. The apparatus as defined in claim 11, further comprising: means for modulating the selected portion of light, wherein the modulation occurs at predetermined frequencies; and   means for determining, based upon the intensity of the light measured by the photo-detector, an intensity of a direct current component, a modulation frequency component and a second harmonic frequency component.   
     
     
       13. The apparatus as defined in claim 10, further comprising a concave reflecting mirror positioned to reflect the light from the light source to the spectroscope, the concave reflecting mirror comprising polished quartz coated with platinum. 
     
     
       14. The apparatus as defined in claim 13, wherein the concave mirror further comprises a top coating of Al--MgF 2 . 
     
     
       15. The apparatus as defined in claim 10, further comprising a sample holder including means for heating and cooling the sample. 
     
     
       16. The apparatus as defined in claim 10, wherein the spectroscope comprises three diffraction gratings. 
     
     
       17. The apparatus as defined in claim 16, further comprising a rotary base on which the spectroscope is mounted, wherein the pre-selected wavelengths are chosen by rotating the rotary base. 
     
     
       18. An apparatus contained within a substantially oxygen-free environment for measuring magneto-optical effects, the apparatus comprising: means for producing light having wavelengths less than 200 nanometers;   means for separating the light into spectral components having preselected wavelengths;   means for polarizing the spectral components of light, and irradiating a sample with the polarized light;   means for applying a magnetic field to the sample;   means for polarizing light which is one of light transmitted by and light reflected from the sample; and   means for detecting an intensity of the light which is one of light transmitted by and light reflected from the sample.   
     
     
       19. The apparatus as defined in claim 18, wherein the means for separating the light into spectral components comprises a spectroscope having three diffraction gratings. 
     
     
       20. The apparatus as defined in claim 19, further comprising means for producing light having wavelengths greater than 200 nanometers to irradiate the sample with wavelengths over a wide frequency range.